1. Field of the Invention
The present invention relates to improvements in the structure for fitting a generator stator to an engine in which a generator stator, working together with a rotor fixed to a crankshaft, is fixed by means of bolts to a plurality of fitting bosses formed on an outside wall of the engine main body supporting the crankshaft.
2. Description of the Prior Art
A structure for fitting a generator stator to an engine is known as disclosed in, for example, Japanese Utility Model Registration Publication No. 63-5420.
An engine is sometimes fitted with a power generator having a different form or capacity due to a change in specification, and in such cases the positions of the fitting bosses which are formed on an outside wall of the engine in order to fix the stators of various types of power generator, also vary.
Therefore, a plurality of types of engine main bodies each having fitting bosses which are dedicated to the stator of the corresponding type of power generator have been made, but this results in a reduction in the manufacturing efficiency of the engine main bodies and it has been difficult to lower their cost.
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a structure for fitting a generator stator to an engine which allows generator stators having different shapes to be fitted selectively to a common engine main body, thus contributing to an enhancement of the manufacturing efficiency of the engine main body.
In order to achieve the above object a first characteristic of the invention is that the structure for fitting a generator stator to an engine is provided, in which a generator stator works together with a rotor fixed to a crankshaft, is fixed by means of bolts to a plurality of fitting bosses formed on an outside wall of an engine main body supporting the crankshaft. In order to selectively fit a first or second generator stator having different shapes from each other to the outside wall of the engine main body, a plurality of first fitting bosses for bolting the first generator stator and a plurality of second fitting bosses for bolting the second generator stator, are provided at different positions on the outside wall.
In accordance with the first characteristic, since the first and second generator stators having different shapes from each other can be fitted selectively to the outside wall of the same engine main body, it is unnecessary to prepare special engine main bodies to fit the first and second generator stators, thus enhancing the manufacturing efficiency of engine main bodies and contributing greatly to a reduction in cost.
Furthermore, a second characteristic of the present invention is that the first and second fitting bosses comprise boss main bodies which are integrally moulded with the outside wall and collars which are detachably superimposed on the boss main bodies.
In accordance with the second characteristic, when the first generator stator is bolted to the first fitting bosses, the collars of the second fitting bosses are removed, and when the second generator stator is bolted to the second fitting bosses, the collars of the first fitting bosses are removed. It is thus possible to avoid interference between the first generator stator and the second fitting bosses and between the second generator stator and the first fitting bosses, and it is therefore possible to position the first and second fitting bosses closely to each other.
Furthermore, a third characteristic of the present invention is that the engine main body comprises a crank case which supports one end part of the crankshaft on one side wall thereof and has an opening part for assembling the crankshaft on another side wall thereof and a case cover which is bolted to the crank case to close the opening part. The first and second fitting bosses are provided on the outside wall of the case cover.
In accordance with the third characteristic, since the size of the case cover having integral first and second fitting bosses is far smaller than the crank case, it can be comparatively easily moulded thus further reducing the cost.